U.S. patent application number 10/337160 was filed with the patent office on 2004-07-08 for junction box and soldering method for printed circuit board of the junction box.
Invention is credited to Choi, Yang Youn, Lee, Cheol Seob, Song, Jong Keun.
Application Number | 20040129765 10/337160 |
Document ID | / |
Family ID | 33030891 |
Filed Date | 2004-07-08 |
United States Patent
Application |
20040129765 |
Kind Code |
A1 |
Lee, Cheol Seob ; et
al. |
July 8, 2004 |
Junction box and soldering method for printed circuit board of the
junction box
Abstract
A printed circuit board junction box including an outer case and
a printed circuit board. The outer case has a top cover and a
bottom cover. The printed circuit board has female and male
electrical terminals mounted in through-holes that extend from an
upper surface to a lower surface of the printed circuit board. One
side of the printed circuit board has only male electrical
terminals. The printed circuit board is soldered by raising a
molten solder container to contact the lower surface of the printed
circuit board. The printed circuit board is turned in a heating
chamber so that the molten solder flows through the through-holes
in the printed circuit board to solder the female and male
electrical terminals to the printed circuit board.
Inventors: |
Lee, Cheol Seob; (Daeku-Si,
KR) ; Choi, Yang Youn; (Ansung-Si, KR) ; Song,
Jong Keun; (Daeku-Si, KR) |
Correspondence
Address: |
JoAnn Dilloway
Barley, Snyder
126 East King Street
Lancaster
PA
17602-2893
US
|
Family ID: |
33030891 |
Appl. No.: |
10/337160 |
Filed: |
January 6, 2003 |
Current U.S.
Class: |
228/259 ;
228/256 |
Current CPC
Class: |
H05K 2201/10295
20130101; H05K 2201/10303 20130101; H05K 1/0263 20130101; B23K 1/08
20130101; H05K 3/3447 20130101; B23K 1/20 20130101; B23K 1/0016
20130101; H05K 7/026 20130101; B23K 2101/42 20180801; B23K 1/008
20130101 |
Class at
Publication: |
228/259 ;
228/256 |
International
Class: |
B23K 031/02 |
Claims
I/we claim:
1. A printed circuit board junction box comprising: an outer case
having a top cover and a bottom cover; and a printed circuit board
having female and male electrical terminals mounted in
through-holes that extend from an upper surface to a lower surface
of the printed circuit board, the printed circuit board having a
wiring pattern and an auxiliary metal pattern that allows current
to flow through the female and male electrical terminals.
2. The printed circuit board junction box of claim 1, wherein the
auxiliary metal pattern includes reinforced metal traces and a bus
bar.
3. The printed circuit board junction box of claim 2, wherein the
bus bar is fixed to an end of the printed circuit board in an
upright position.
4. The printed circuit board junction box of claim 1, wherein the
auxiliary metal pattern is formed on the lower surface of the
printed circuit board.
5. The printed circuit board junction box of claim 1, wherein only
male electrical terminals are mounted on the lower surface of the
printed circuit board.
6. The printed circuit board junction box of claim 1, wherein a
plurality of the female and male electrical terminals have
auxiliary connection portions that are received in auxiliary
through-holes in the printed circuit board.
7. The printed circuit board junction box of claim 1, wherein the
female and male electrical terminals are received in the printed
circuit board such that a portion of the female and male electrical
terminals projects from an opposing surface of the printed circuit
board.
8. The printed circuit board junction box of claim 1, wherein the
through-holes are configured so that when the female and male
electrical terminals are fitted in the through-holes a molten
solder applied to a surface of the printed circuit board flows
through the through-holes to an opposing surface of the printed
circuit board.
9. A printed circuit board junction box comprising: an outer case
having a top cover and a bottom cover; and a printed circuit board
having female and male electrical terminals mounted in
through-holes that extend from an upper surface to a lower surface
of the printed circuit board and one side of the printed circuit
board has only male electrical terminals.
10. The printed circuit board junction box of claim 9, wherein the
printed circuit board has a wiring pattern and an auxiliary metal
pattern including reinforced metal traces and a bus bar that allows
current to flow through the female and male electrical
terminals.
11. The printed circuit board junction box of claim 10, wherein the
bus bar is fixed to an end of the printed circuit board in an
upright position.
12. The printed circuit board junction box of claim 10, wherein the
auxiliary metal pattern is formed on the lower surface of the
printed circuit board.
13. The printed circuit board junction box of claim 9, wherein a
plurality of the female and male electrical terminals have
auxiliary connection portions that are received in auxiliary
through-holes in the printed circuit board.
14. The printed circuit board junction box of claim 9, wherein the
female and male electrical terminals are received in the printed
circuit board such that a portion of the female and male electrical
terminals projects from an opposing surface of the printed circuit
board.
15. The printed circuit board junction box of claim 9, wherein the
through-holes are configured so that when the female and male
electrical terminals are fitted in the through-holes a molten
solder applied to a surface of the printed circuit board flows
through the through-holes to an opposing surface of the printed
circuit board.
16. A method for soldering a printed circuit board of a junction
box, comprising: mounting female and male electrical terminals in
through-holes on an upper and lower surface of a printed circuit
board; applying molten solder to the lower surface of the printed
circuit board; turning the printed circuit board in a heating
chamber so that molten solder flows through the through-holes in
the printed circuit board to solder the female and male electrical
terminals to the printed circuit board.
17. The method of claim 9, further comprising pre-heating the
printed circuit board.
18. The method of claim 9, wherein only male electrical terminals
are mounted to the lower surface.
19. The method of claim 9, further comprising moving a molten
solder container upward toward the lower surface of the printed
circuit board.
20. The method of claim 9, wherein an auxiliary metal pattern is
formed on the lower surface of the printed circuit board.
Description
BACKGROUND OF THE INVENTION
[0001] The invention relates to junction boxes and, more
particularly, to an arrangement and method of soldering electrical
terminals to a printed circuit board in a junction box.
DESCRIPTION OF THE PRIOR ART
[0002] In order to distribute electric power in accordance with
different modes in a vehicle, junction boxes adapted to protect
wiring in the vehicle are installed in a vehicle compartment and an
engine compartment. Conventional junction boxes include a plurality
of printed circuit boards (PCBs) vertically arranged in parallel.
The PCBs are electrically connected by soldering connecting pins
that are inserted into each PCB to each other along edges of the
PCB. Because the conventional junction box uses a plurality of
PCBs, the junction box takes up a lot of space in the vehicle.
Further, because the connecting pins of the PCBs are soldered to
each other in order to electrically connect the PCBs, the soldering
process must be performed multiple times causing an increase in
manufacturing time and cost.
[0003] In order to solve the above-mentioned problems, Korean
Utility Model Publication No. 2000-0211471 teaches a junction box
having a printed circuit board type structure. As shown in FIG. 6,
the junction box includes an outer case having a top cover 110 and
a bottom cover 120. The top cover 110 is configured to receive
various devices, such as, fuses 111, 112 and relays 113, 114. The
bottom cover 120 is configured to receive input and output
connectors 121, 122. Disposed within the outer case is a metal bus
layer 115, an insulating plate 116, and a single PCB 119.
Electrical terminals 117, 118 are connected to the PCB 119. Each of
the electrical terminals 118, which may be male electrical
terminals, is fixed to a lower surface of the PCB 119 by means of
soldering. Each of the electrical terminals 117, which may be
male/female (MF) terminals, is mechanically inserted in an upper
surface of the PCB 119. The electrical terminals 117, 118,
therefore, can be installed on both surfaces of the PCB 119 at one
time by soldering. However, it is impossible to solder the
electrical terminals 117, 118 to the PCB 119 at one time with a
wave soldering process using the waves of a liquid solder contained
in a liquid solder container. The soldering of the electrical
terminals 117, 118 may only be achieved using a more complex
soldering process.
[0004] Since the MF terminals 117 are mechanically inserted in the
PCB 119 at one surface of the PCB 119, the printed circuit board
type junction box of the prior art may be broken down or may have
unstable electrical connections due to an external impact applied
thereto during use in the vehicle or when devices such as the
relays 113, 114 or fuses 111, 112 are inserted or removed from the
MF terminals 117. Further, it is necessary to use the insulating
plate 116 in order to support the metal bus layer 115 while
electrically isolating the metal bus layer 115 from the PCB 119
arranged beneath the metal bus layer 115. As a result, the entire
structure and assembly process of the junction box is complicated
and the size of the junction box is increased. Further,
manufacturing costs are increased due to the additional cost
incurred for the production and assembly of the insulating plate
116 and metal bus layer 115.
[0005] It is therefore desirable to develop a junction box having a
printed circuit board for a simple and compact structure that
dispenses with the metal bus layer and insulating plate required in
conventional structures. It is also desirable to develop a junction
box having a printed circuit board structure where electrical
terminals can be mounted on the PCB using one step and are easily
and simply soldered to the PCB while exhibiting an improvement in
durability and impact resistance. It is further desirable to
provide a junction box having a printed circuit board structure
where electrical terminals mounted to an upper and lower surface of
the PCB are reliably electrically connected and exhibit a high
conductivity.
SUMMARY OF THE INVENTION
[0006] The invention relates to a printed circuit board junction
box. The printed circuit board junction box includes an outer case
and a printed circuit board. The outer case has a top cover and a
bottom cover. The printed circuit board has female and male
electrical terminals fitted in through-holes that extend from an
upper surface to a lower surface of the printed circuit board,
wherein one side of the printed circuit board has only male
electrical terminals.
[0007] The invention further relates to a method for soldering a
printed circuit board of a junction box. Female and male electrical
terminals are mounted in through-holes on an upper and lower
surface of a printed circuit board. Molten solder is applied to the
lower surface of the printed circuit board. The printed circuit
board is turned in a heating chamber so that the molten solder
flows through the through-holes in the printed circuit board to
solder the female and male electrical terminals to the printed
circuit board.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is an exploded perspective view of a junction
box;
[0009] FIG. 2 is a perspective view of an upper surface of a
printed circuit board (PCB) of the junction box;
[0010] FIG. 3 is an enlarged perspective view of female electrical
terminals inserted in the PCB of FIG. 2;
[0011] FIG. 4 is a perspective view of a lower surface of the PCB
of FIG. 2;
[0012] FIG. 5 is a flow chart showing a method for soldering the
PCB of FIG. 2; and
[0013] FIG. 6 is an exploded perspective view of a conventional
junction box.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0014] FIG. 1 shows a junction box according to the present
invention. As shown in FIG. 1, the junction box has an outer case
including a top cover 10 and a bottom cover 30 and a printed
circuit board (PCB) 20. The top cover 10 has mounting holes for
mounting devices, such as, fuses 11, 12 and relays 13, 14. The PCB
20 is mounted with a plurality of female electrical terminals 21
and male electrical terminals 22, 23. The bottom cover 30 is
adapted to support the PCB 20 and is provided with input and output
connectors 31, 32. Since the top cover 10 and the bottom cover 30
are well known in the art, no further description thereof will be
given.
[0015] The PCB 20 and the female and male electrical terminals 21,
22, 23 will now be described in greater detail. As shown in FIGS. 2
and 4, the PCB 20 has wiring patterns 24 coated on an upper and
lower surface of the PCB 20. The wiring patterns 24 are distributed
over the entire surface of the PCB 20 and are separated by
minimum-size gaps that insulate adjacent wiring patterns 24 and
provide mechanical mounting areas. Each wiring pattern 24 is formed
to have a large width so that the female and male electrical
terminals 21, 22, 23 have optimal conductivity when connected to
the PCB 20.
[0016] Through-holes 25 adapted to receive the female and male
electrical terminals 21, 22, 23 extend through the PCB 20 from the
upper surface to the lower surface. The female and male electrical
terminals 21, 22, 23 are received in the through-holes 25 so that a
portion of the female and male electrical terminals 21, 22, 23
slightly projects from an opposing surface of the PCB 20. Each
through-hole 25 is configured so that a molten solder applied to
one surface of the PCB 20 flows through the through-hole 25 to the
opposing surface of the PCB 20 when the female and male electrical
terminals 21, 22, 23 are fitted in the through-holes 25 to allow
the female and male electrical terminals 21, 22, 23 to be soldered
at the projected portion.
[0017] As shown in FIGS. 3 and 4, auxiliary through-holes 26, 26'
may be formed near each of the through-holes 25. The auxiliary
through-holes 26, 26' reduce electrical connection errors caused by
contact errors generated during fitting and soldering the female
and male electrical terminals 21, 22 to the PCB 20. The auxiliary
through-holes 26, 26' also reduce electrical connection errors
caused by contact errors generated between the PCB 20 and the
female and male electrical terminals 21, 22 due to an external
impact applied to the junction box during use of the junction box
in a vehicle. The auxiliary through-holes 26, 26' can reliably
maintain desired electrical connections even if the mechanical
connection between the PCB 20 and the female electrical terminals
21 becomes unstable when various devices such as fuses 11, 12 or
relays 13, 14 are mounted to the female electrical terminals
21.
[0018] As shown in FIGS. 2 and 3, the female and male electrical
terminals 21, 22 have auxiliary connection portions 21', 22',
respectively. The auxiliary connection portions 21', 22' are
inserted into the auxiliary through-holes 26, 26', respectively, so
that the female and male electrical terminals 21, 22 are firmly
supported by the PCB 20. The auxiliary connection portions 21', 22
increase the contact area of each connecting terminal 21, 22 on the
PCB 20 to provide an effective electrical connection.
[0019] As shown in FIG. 4, auxiliary metal patterns on the wiring
patterns 24 may be formed on a lower surface of the PCB 20. The
auxiliary metal patterns may comprise metal traces 28 and a metal
bus bar 27. Each of the metal traces 28 corresponds to an area
along which an additional pattern formed along a part of each
pattern on the PCB 20 is subjected to a soldering process. The
metal bus bar 27 is mounted to the PCB 20 at one end of the PCB 20.
The metal bus bar 27 may be fixed to the PCB 20 in an upright
position by means of soldering so that an increased number of the
female and male electrical terminals 21, 22, 23 may be mounted to
the PCB 20. The metal bus bar 27 and metal traces 28 allow current
to flow smoothly through the female and male electrical terminals
21, 22, 23, which require a large amount of current.
[0020] A method for soldering the female and male electrical
terminals 21, 22, 23 to the PCB 20 of the junction box will now be
described in greater detail with reference to the flow chart shown
in FIG. 5. As shown at s1, the female and male electrical terminals
21, 22, 23 are mounted to the PCB 20. The female electrical
terminals 21 are mounted on the upper surface of the PCB 20 by
inserting the female electrical terminals 21 into the through-holes
25. The male electrical terminals 21, 22 are mounted on the lower
surface of the PCB 20 by inserting the male electrical terminals
22, 23 into the through-holes 25. It is preferable that only the
male electrical terminals 22, 23 are mounted to the lower surface
of the PCB 20.
[0021] As shown at s2, the PCB 20 is pre-heated. The PCB 20 is
preheated so that the PCB 20 is protected during the soldering
process and achieves optimal soldering results. As shown at s3, the
pre-heated PCB 20 is dipped into a molten solder container so that
the lower surface of the PCB 20 on which the male electrical
terminals 22, 23 are exposed contacts the molten solder. Unlike the
conventional method where the PCB 20 would be dipped into the
molten liquid container by moving the PCB 20 downward into the
molten liquid container, the PCB 20 is fixed and the molten liquid
container is moved upward so that the molten solder is applied to
the lower surface of the PCB 20 and moved downward after the
completion of the soldering process. At step s3, the molten solder
is applied to each portion of the female electrical terminals 21
that projects from the lower surface of the PCB 20 through the
associated through-hole 26.
[0022] Since the soldering process is carried out in this fashion,
it is possible to effectively turn over the PCB 20 after completion
of the soldering process, as shown at s4. The soldered PCB 20 is
turned over in a heating chamber. When the soldered PCB 20 is
turned over, the molten solder applied to each of the male
electrical terminals 22, 23 flows to the portion of the male
electrical terminals 22, 23 that projects from the upper surface of
the PCB 20 via the associated through-holes 26' to solder the
projected portion.
[0023] As shown at s5, the heated PCB 20 is then cooled and tested.
By preventing an abrupt temperature change of the PCB 20, the
solder applied to the PCB 20 is prevented from accumulating on the
male electrical terminals 22, 23. Accordingly, it is possible to
reliably fix each of the female and male electrical terminals 21,
22, 23 inserted into the PCB 20 by a single soldering process.
[0024] The junction box of the present invention has a simple
structure comprising the metal bus bar 27 and the metal traces 28
in place of a metal bus layer 115 and insulating plate 116 as
required in the conventional structure shown in FIG. 6.
Accordingly, it is possible to simplify the structure of the
junction box while reducing the number of elements, thereby
reducing the manufacturing cost. Auxiliary through-holes 26, 26'
are formed on the PCB 20 near each of the through-holes 25 to
ensure a reliable and easy electrical connection. The PCB 20
carries, at one surface thereof, only the male electrical terminals
22, 23. This configuration enables the female and male electrical
terminals 21, 22, 23 to be fixed on the upper and lower surfaces of
the PCB 20 using a single soldering process. As a result,
manufacturing time and cost may be reduced.
[0025] The foregoing illustrates some of the possibilities for
practicing the invention. Many other embodiments are possible
within the scope and spirit of the invention. It is, therefore,
intended that the foregoing description be regarded as illustrative
rather than limiting, and that the scope of the invention is given
by the appended claims together with their full range of
equivalents.
* * * * *